Many types of surgery, such as, for example, spinal surgery, require a surgeon to remove sections of bone, cartilage and/or related biological matter. In response to this need, many surgical instruments have been developed. Typically, when using known instruments, the surgeon will use the instrument to remove or excise a small section or portion of tissue material. The instrument is then removed from the surgical site and the tissue material is then removed from the instrument by an assistant. The process is then repeated, typically a very large number of times. Often the excised portions of tissue material need to be retained for subsequent use by the surgeon, for example for use as a graft material in fusion procedures. Accordingly, they need to be kept safe during the procedure.
It will be appreciated that the need to have the portion of tissue material removed from the instrument after each excision is time consuming and repetitive. In addition, in procedures where the tissue to be removed is located close to areas which the surgeon wishes to avoid, the process of completely re-positioning the instrument before each excision is also time consuming and can result in fatigue of the surgeon.
A number of solutions to this problem have been proposed. In U.S. Pat. No. 5,451,227, the inventor proposed a rongeur which includes a hollow body cavity into which the excised portions of biological material, such as bone portions, are urged in use. Such an arrangement allows for the surgeon to use the rongeur to make multiple excisions. After the use of the rongeur is complete, the bone portions may be removed from the hollow cavity by an assistant, using pick or obdurator. This is time consuming and may result in the damage of the bone portions. Furthermore, the cavity has a finite cavity and the volume of bone that the surgeon needs to remove may exceed the capacity of the cavity. There thus exists a need to store more volume of bone that can be accommodated by the rongeur itself.
US 2011/0190773 and U.S. Pat. No. 5,766,177 both disclose a rongeur which includes a replaceable combination of a cutting tip and a bone storage member. By replacing the cutting tip every time the bone storage member becomes full, the rongeur maintains a very sharp cutting tip. However, it makes replacing the combined cutting tip and storage member very expensive. It is also time consuming and cumbersome to replace the combined cutting tip and storage member each time, as the cutting tip must be precisely aligned with the base plate to ensure an accurate cut of the biological material placed between the base plate and the cutting tip.
The present invention seeks to address the problems discussed above.